Active bulkhead corner with enhanced commodity discharge

ABSTRACT

An active bulkhead corner unit with a support surface that faces the cargo and inflatable bags located underneath the support surface. The inflatable bags occupy the space between the support surface, the floor of the container, and the adjacent walls of the container. A vibrating mechanism such as a flutter valve is attached to the pressure pump to create rapid variations in pressure which in turn cause the inflatable bag and the support surface to vibrate against the cargo, disturbing the cargo and enhancing discharge flow. The bulkhead corner can be an independent unit or integrated with a liner.

BACKGROUND OF THE INVENTION

1. Technical Field

The present invention relates to the loading and unloading of flowablecargo transported in lined or unlined bulk cargo containers. Inparticular, it relates to inflatable corner bag assemblies for use inguiding bulk commodity materials to an outlet port in a cargo transportbulkhead.

2. Background Art

Transportation of containers for bulk commodity products (grains, etc)have been implemented using a variety transport vehicles, such astrucks, railroads, and ships. An important economic factor in thetransportation of bulk commodities is the speed and ease with which thecommodities are loaded onto and unloaded from the container.

Typical methods of loading and unloading the containers are pressuresystems such as pumps to force commodities into the container duringloading and to provide suction to remove the commodities duringunloading. Another popular method is the use of gravity mechanisms. Forexample, gravity may be used to unload a container by tilting thecontainer such that the bulk commodity flows toward a discharge door atone end of the container.

While both of these methods are generally effective, the unloadingprocess can be improved by more precisely controlling the direction ofthe bulk material as it flows toward the discharge door. In the priorart approach of merely raising the container to allow most of the bulkcommodity to flow out results in some of the commodity remaining in thecorners of the container. This creates the additional labor expense ofmanually removing the residual commodity trapped in the corners. Inaddition to the labor expense required to remove the residual commodityproduct from the corners, the economic efficiency of the container andtransport vehicle is reduced due to the delay involved with thisadditional step in the unloading procedure.

This problem was addressed in U.S. Pat. No. 4,799,607 to Podd whereinrigid angled corners, hinged to a bulkhead, were used to direct thecommodity flow in the direction of the discharge door. This approachalleviated the problem associated with accumulation of commodity residuein the corners of the container.

While addressing the basic desirability of controlling product flow inbulk commodity container systems during unloading, the prior art hascentered on passive systems such as a stationary corner. The prior arthas not provided an active corner system which assists the flowing ofcargo during discharge by active inducement of vibration to reducesettling of cargo and increase the motion of individual cargo particles.

SUMMARY OF THE INVENTION

The present invention solves the foregoing problems by providinginflatable bulkhead corner units which have a rigid or flexible surfacethat faces the cargo and inflatable bags located underneath the surface.The inflatable bags occupy the space between the rigid surface, thefloor of the container, and the adjacent walls of the container. Avibrating mechanism such as a flutter valve is attached to the pressurepump to create rapid variations in pressure which in turn cause theinflatable bag and the rigid surface to vibrate against the cargo,disturbing the cargo and enhancing discharge flow.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram of a prior art rigid corner.

FIG. 2 is an interior view of a bulkhead equipped with aninflatable/corner unit.

FIG. 3 is a detailed cutaway interior view of the bulkhead shown in FIG.2.

FIG. 4 is an exterior view of a bulkhead, and an inflatable corner unit.

FIG. 5 is an exterior view of a bulkhead, an inflatable corner unit, anda liner.

FIG. 6 is a cutaway exterior view of a container showing a bulkhead,flutter valves, inflatable corner units, a liner, and a pressure pump.

FIG. 7 is an alternative embodiment showing flutter valves, inflatablecorner units, and liner integrated into a single device.

FIG. 8 is an alternative embodiment showing an inflatable bag and rigidsurface integrated into a single device.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIG. 1, this figure shows a prior art approach using rigidcorners 104. Bulkhead 102 has discharge door 106 located at its base toallow discharge of cargo from the liner. Load/Vent holes 108 are locatednear the top of the bulkhead. Rigid corners 104 are attached at thesides of the bulkhead. The slope of the corners directs the bulk cargoto discharge door 106 such that portions of the cargo are not trapped inthe corners of the container when the container is unloaded.

FIG. 2 illustrates the inflatable corner units 202 used by the inventiondisclosed herein. For ease of illustration, some structural details ofcorner units 202 were omitted in FIG. 2. These details will be morefully discussed below, in regard to FIG. 3. The corner units 202 areshown inflated for use with bulk cargo. When unloading the cargo, thecorner units 202 provide the same directional control over cargo flow asthe prior art rigid corners. However, in addition to controlling cargoflow direction as is done by prior art devices, the active corner units202 of this invention enhance cargo discharge flow by vibrating duringdischarge to discourage settling of cargo and further to enhance flowrate. The vibration effect and the structural details of the cornerunits 202 will be discussed more fully below. This specification usesthe term "air" pressure to describe the pressure levels inside thecorner units. For the purposes of this disclosure, the term "air"defines not only ambient air, but any suitable gas which can besubstituted for ambient air to achieve the desired result.

For ease of illustration, the support surfaces 204 of corner units 202which face the cargo are illustrated as rigid surfaces. Indeed, onemethod of constructing these surfaces is to utilize a hard material suchas plywood, plastic, etc. However, those skilled in the art willrecognize that any number of flexible materials may also be usedproviding that the resulting surface can effectively guide the cargo todischarge door 106 without excessive deformation. Examples of such amaterial would be heavy gauge polyethylene or polypropylene sheets inthe approximate range of sixty (60) mils in thickness. Therefore, forthe purpose of this disclosure, it is understood that the term "support"surfaces encompasses both materials which form "rigid" surfaces as wellas surfaces which are "flexible," such as the heavy gauge polyethyleneand polypropylene sheets discussed above.

FIG. 3 shows a closeup cutaway view of the corner units 202. Cornerunits 202 have a support surface 204 which faces the cargo or liner 502.In the preferred embodiment, support surface 204 is attached to bulkhead102 by hinge 306. However, those skilled in the art will recognize thatany number of conventional methods of securing corner units 202 may beemployed. Underneath support surface 204 is inflatable bag 304. Duringunloading, inflatable corner bags 304 create a vibration under controlof flutter valve 404 (shown in FIG. 4) and pump 602 (shown in FIG. 6).The preferred inflation medium is contemplated as air, but any suitablegas, liquid, or air may be used to provide internal pressure. Byproviding a support surface 204, undesirable changes in the surfaceshape of corner units 202 are avoided. In addition, the effect of thevibration is maximized by the support surface 204 in that the vibrationis not dampened as it might be if a flexible surface were used insteadof support surface 204.

Inflatable bags 304 may be fabricated from any suitable material such aspolyethylene, polypropylene, vinyl, kraft paper laminates, etc. The onlyrequirement is that the material be suitable for the particular cargo(i.e., it will not react or contaminate cargo such as food, etc.).Inflatable bags 304 are secured to the bulkhead 102 and/or container(not shown) by straps or tie downs (not shown). Those skilled in the artwill recognize that any other suitable method of securing inflatablebags 304 may be used. For example, adhesive could be used to secure theinflatable bags 304 to bulkhead 102. Also, inflatable bags 304 can beconstructed as an independent unit or integrated with support surface204. In an alternative embodiment, liner 502, inflatable bag 304, andsupport surface 204 may be integrated into a single disposable unit.

Support surface 204 can be fabricated from any material, such as wood,corrugated board, metal, plastics, etc. The preferred embodimentenvisions plywood, which combines strength with low cost.

FIG. 4 shows an exterior view of bulkhead 102. Inflatable corner unit202 is shown on the interior side of bulkhead 102. Apertures 402 areprovided in bulkhead 102 to allow easy access to the flutter valves 404of inflatable corner bags 202. Flutter valves create a rapid start stopmotion to air flow entering corner units 202. The effect of the air flowvariation is to create a vibration in inflatable bags 304 which is inturn applied to the cargo through support surface 204. Flutter valves404 are well known in the art.

FIG. 5 shows a liner 502 used in conjunction with the bulkhead 102 andthe inflatable corner units 202. Tubes 504 provide access to load/ventliner 502. As can be seen, inflatable corner units 202 lift the base ofliner 502 resulting in a sloping of the liner bag toward the dischargedoor 106. For ease of illustration, inflatable corner bags 202 wereshown throughout this specification as devices which are separate fromthe bulkhead. However, they can easily be integrated with bulkhead 102such that bulkhead 102 and inflatable corner units 202 comprise a singledevice for ease of installation. Likewise, those skilled in the art willrecognize that inflatable corner units 202 can also be manufactured aspart of liner 502. Whether the inflatable corner units 202 areindependent devices, part of the bulkhead 102, or part of the liner 502is of no concern so long as the inflatable corner units 202 areaccessible for connection of a pump 602 to the flutter valve 404 andcapable of vibration to enhance the flow rate of the bulk commoditycargo.

Flutter valve 404 can be integrated with a corner unit 202 orimplemented as a separate unit. For ease of illustration, the fluttervalve 404 is shown as part of corner units 202. However, the preferredembodiment envisions the flutter valve 404 as a separate unit outside ofthe container and incorporated into pump 602 which results in lower costthan integrating flutter valve 404 in corner unit 202 because it isreusable if not integrated into corner units 202. Further, theinflatable corner units 202 were shown as approximately equal in size.In the event the discharge door 106 is offset to one side of bulkhead102, the size and angle of inflatable corner units 202 may vary toensure that adequate control of flow direction is obtained by bothinflatable corner bags 202. It is also possible to design a bulkhead 102with discharge door 106 offset to one side of bulkhead 102 such thatonly a single corner unit 202 is required.

While flutter valves 404 are used in the preferred embodiment, anysuitable vibration generation means can be used. For example, mechanicalvibration generators, or sonic generators using sonic or ultrasonicfrequencies can be used. In addition, so long as the desired amount ofvibration is achieved, the vibration means can be attached to cornerunits 202, to the inside or outside of bulkhead 102, or to the wall orfloor of container 604 (shown in FIG. 6). The only requirement is thatcorner units 202 be caused to vibrate such that cargo flow is enhanced.

FIG. 6 a cutaway view showing liner 502 installed in container 604 whichhas first and second side walls 608, 610, and floor 612. Bulkhead 102 isshown mounted in the end of container 604 between side walls 608, 610. Acorner unit 202 is shown mounted at the intersection of first side wall608, floor 612 and bulkhead 102. Load/vent tubes 504 provide the loadingpath for the cargo. Discharge port 106 provides the discharge path forthe cargo. Pump 602 provides a source of air pressure which is pumpedthrough hoses 606 to flutter valves 404. While separate pumps 602 can beused for each flutter valve 404, the preferred embodiment envisions asingle pump 602 driving both flutter valves 404. Flutter valve 404 andpump 602 can be stored in any convenient location at the receiving siteor on the container vehicle. Where appropriate, pump 602 can be storedat the destination location and shared among many vehicles. Air pressurepumps are well known in the art. In practice, a vehicle operator canquickly attach pump 602 and flutter valves 404 from outside of thevehicle to assist in unloading the cargo. A preferable method is tointegrate flutter valve 404 and pump 602 into a single unit tofacilitate ease of use.

FIG. 7 shows an alternative embodiment in which the liner 502 and cornerunit 202 are integrated into a single device. Discharge channel 702shows a typical channel which would extend through discharge door 106for unloading. In this embodiment, support surface 204 is held in placeby heat sealing the inflatable corner bag 304 to liner 502 around theperiphery of support surface 204. Heat sealing methods for linermaterial are well known in the art.

FIG. 8 shows an alternative embodiment in which the inflatable bag 304and support surface 204 are integrated into a single device. In thisembodiment, a flexible layer 804 of material, preferably the same asthat used for the inflatable bag, is placed over the side of the supportsurface 204 which faces away from inflatable bag 304. Flexible layer 804is heat sealed to inflatable bag 304 along seam 802, encapsulatingsupport surface 204. Heat sealing methods for liner material are wellknown in the art. For ease of illustrating the sealing of flexible layer804 to seam 802, inflatable bag 304 was shown as being larger in sizethan support surface 204. However, in the preferred embodiment, flexiblelayer 804 will wrap around the side of support surface 204 to seal tosmaller inflatable bag 304 at seam 802.

As mentioned above in the discussion of FIG. 2, flexible material suchas a thick layer of polyethylene or polypropylene can also be used toconstruct surface 204. When using these materials, and in addition tothe encapsulation method discussed above, a variety of methods can beused to join surfaces 204 to corner units 202, including heat sealing,chemical bonding, adhesives, etc.

An alternative embodiment of corner units 202 can also be employed whichutilizes reinforced layers of material to provide protection againstcorner unit 202 failure. In this embodiment, woven layers ofpolyethylene or polypropylene can be laminated to the outside of cornerunits 202 to increase the structural strength of corner units 202. Whilethe preferred embodiment envisions layers approximately four (4) to six(6) mils thick, the thickness of these layers is not important and anysuitable thickness may be selected so long as the ability of cornerunits 202 to vibrate is not significantly impaired.

While the invention has been described with respect to a preferredembodiment thereof, it will be understood by those skilled in the artthat various changes in detail may be made therein without departingfrom the spirit, scope, and teaching of the invention. For example, thevibration mechanism may vary, support corner and inflatable corner bagconstruction materials can vary, and the corners may be independentdevices or integrated into a liner. Accordingly, the invention hereindisclosed is to be limited only as specified in the following claims.

I claim:
 1. An active bulkhead corner for use with a cargo containerbulkhead, comprising:an inflatable bag, positioned upon inflation in acorner of a cargo container at an intersection of a floor of the cargocontainer, a first wall of a cargo container bulkhead and a second sidewall of the cargo container, the bag configured upon inflation todisplace cargo from the corner of the cargo container; a supportsurface, the support surface having one side in contact with theinflatable bag, the support surface further having a first edgesubstantially parallel to the first wall of the cargo containerbulkhead, a second edge substantially parallel to the second side wallof the cargo container, and a third edge substantially parallel to thefloor of the cargo container.
 2. An active bulkhead corner, as in claim1, wherein the support surface and the inflatable bag are integratedinto a single unit.
 3. An active bulkhead corner, as in claim 2, furthercomprising:a flexible layer located above the support surface on theside opposite the inflatable bag; a seal attaching the flexible layer tothe inflatable bag around the periphery of the support surface such thatthe support surface is enclosed by the flexible layer and the inflatablebag.
 4. An active bulkhead corner, as in claim 1, further comprisingattachment means to provide an input for air pumped under pressure tothe inflatable bag.
 5. An active bulkhead corner, as in claim 4, furthercomprising means to vibrate the inflatable bag when the inflatable bagis in contact with the support surface such that the inflatable bagcauses the support surface to vibrate.
 6. An active bulkhead corner, asin claim 5, wherein the means to vibrate the inflatable bag includes aflutter valve.
 7. An active bulkhead corner, as in claim 5, wherein themeans to vibrate the inflatable bag includes a mechanical vibrator. 8.An active bulkhead corner, as in claim 5, wherein the means to vibratethe inflatable bag includes a sonic vibrator.
 9. An active bulkheadcorner, as in claim 1, further comprising means to vibrate theinflatable bag when the inflatable bag is in contact with the supportsurface such that the inflatable bag causes the support surface tovibrate.
 10. An active bulkhead corner, as in claim 9, wherein the meansto vibrate the inflatable bag includes a flutter valve.
 11. An activebulkhead corner, as in claim 9, wherein the means to vibrate theinflatable bag includes a mechanical vibrator.
 12. An active bulkheadcorner, as in claim 9, wherein the means to vibrate the inflatable bagincludes a sonic vibrator.
 13. An active bulkhead corner, as in claim 2,further comprising attachment means to provide an input for air pumpedunder pressure to the inflatable bag.
 14. An active bulkhead corner, asin claim 13, further comprising means to vibrate the inflatable bag whenthe inflatable bag is in contact with the support surface such that theinflatable bag causes the support surface to vibrate.
 15. An activebulkhead corner, as in claim 14, wherein the means to vibrate theinflatable bag includes a flutter valve.
 16. An active bulkhead corner,as in claim 14, wherein the means to vibrate the inflatable bag includesa mechanical vibrator.
 17. An active bulkhead corner, as in claim 14,wherein the means to vibrate the inflatable bag includes a sonicvibrator.
 18. An active bulkhead corner, as in claim 2, furthercomprising means to vibrate the inflatable bag when the inflatable bagis in contact with the support surface such that the inflatable bagcauses the support surface to vibrate.
 19. An active bulkhead corner, asin claim 18, wherein the means to vibrate the inflatable bag includes aflutter valve.
 20. An active bulkhead corner, as in claim 18, whereinthe means to vibrate the inflatable bag includes a mechanical vibrator.21. An active bulkhead corner, as in claim 18, wherein the means tovibrate the inflatable bag includes a sonic vibrator.
 22. A linerassembly having an integrated active bulkhead corner for use with acargo container, comprising:a liner; an inflatable bag, attached to theliner and positioned upon inflation in a corner of the cargo containerat an intersection of a floor of the cargo container, a first wall of acargo container bulkhead and a second side wall of the cargo container,the bag configured upon inflation to displace cargo from the corner ofthe cargo container; a support surface, the support surface having oneside in contact with the inflatable bag and the other side in contactwith the liner, the support surface further having a first edgesubstantially parallel to the first wall of the cargo containerbulkhead, a second edge substantially parallel to the second side wallof the cargo container, and a third edge substantially parallel to thefloor of the cargo container.
 23. A liner assembly, as in claim 22,wherein the support surface and the inflatable bag are integrated into asingle unit.
 24. A liner assembly, as in claim 23, further comprising:aflexible layer located above the support surface on the side oppositethe inflatable bag; a seal attaching the flexible layer to theinflatable bag around the periphery of the support surface such that thesupport surface is enclosed by the flexible layer and the inflatablebag.
 25. A liner assembly, as in claim 22, further comprising attachmentmeans to provide an input for air pumped under pressure to theinflatable bag.
 26. A liner assembly, as in claim 25, further comprisingmeans to vibrate the inflatable bag when the inflatable bag is incontact with the support surface such that the inflatable bag causes thesupport surface to vibrate.
 27. A liner assembly, as in claim 26,wherein the means to vibrate the inflatable bag includes a fluttervalve.
 28. An active bulkhead corner, as in claim 26, wherein the meansto vibrate the inflatable bag includes a mechanical vibrator.
 29. Anactive bulkhead corner, as in claim 26, wherein the means to vibrate theinflatable bag includes a sonic vibrator.
 30. A liner assembly, as inclaim 22, further comprising means to vibrate the inflatable bag whenthe inflatable bag is in contact with the support surface such that theinflatable bag causes the support surface to vibrate.
 31. A linerassembly, as in claim 30, wherein the means to vibrate the inflatablebag includes a flutter valve.
 32. An active bulkhead corner, as in claim30, wherein the means to vibrate the inflatable bag includes amechanical vibrator.
 33. An active bulkhead corner, as in claim 30,wherein the means to vibrate the inflatable bag includes a sonicvibrator.
 34. A liner assembly, as in claim 23, further comprisingattachment means to provide an input for air pumped under pressure tothe inflatable bag.
 35. A liner assembly, as in claim 34, furthercomprising means to vibrate the inflatable bag when the inflatable bagis in contact with the support surface such that the inflatable bagcauses the support surface to vibrate.
 36. A liner assembly, as in claim35, wherein the means to vibrate the inflatable bag includes a fluttervalve.
 37. An active bulkhead corner, as in claim 35, wherein the meansto vibrate the inflatable bag includes a mechanical vibrator.
 38. Anactive bulkhead corner, as in claim 35, wherein the means to vibrate theinflatable bag includes a sonic vibrator.
 39. A liner assembly, as inclaim 23, further comprising means to vibrate the inflatable bag whenthe inflatable bag is in contact with the support surface such that theinflatable bag causes the support surface to vibrate.
 40. A linerassembly, as in claim 39, wherein the means to vibrate the inflatablebag includes a flutter valve.
 41. An active bulkhead corner, as in claim39, wherein the means to vibrate the inflatable bag includes amechanical vibrator.
 42. An active bulkhead corner, as in claim 39,wherein the means to vibrate the inflatable bag includes a sonicvibrator.
 43. A method for actively enhancing cargo flow whiledischarging cargo from a cargo container, comprising:inflating aninflatable bag, positioned upon inflation in a corner of the cargocontainer at an intersection of a floor of the cargo container, a firstwall of a cargo container bulkhead and a second side wall of the cargocontainer, the bag configured upon inflation to displace cargo from thecorner of the cargo container; locating a support surface in the cornerof a cargo container, the support surface having one side in contactwith the inflatable bag, the support surface further having a first edgesubstantially parallel to the first wall of the cargo containerbulkhead, a second edge substantially parallel to the second side wallof the cargo container, and a third edge substantially parallel to thefloor of the cargo container; and vibrating the inflatable bag when theinflatable bag is in contact with the support surface such that theinflatable bag causes the support surface to vibrate.
 44. A method, asin claim 43, further including the step of vibrating the inflatable bagwhen the inflatable bag is in contact with the support surface such thatthe inflatable bag causes the support surface to vibrate.
 45. A method,as in claim 44, further including the step of vibrating the inflatablebag with a flutter valve.
 46. A method, as in claim 44, furtherincluding the step of vibrating the inflatable bag with a mechanicalvibration generator.
 47. A method, as in claim 44, further including thestep of vibrating the inflatable bag with a sonic generator.
 48. Anactive bulkhead corner, as in claim 5, wherein the means to cause thesupport surface to vibrate is attached to the bulkhead.
 49. An activebulkhead corner, as in claim 5, wherein the means to cause the supportsurface to vibrate is attached to the cargo container.
 50. An activebulkhead corner, as in claim 9, wherein the means to cause the supportsurface to vibrate is attached to the bulkhead.
 51. An active bulkheadcorner, as in claim 9, wherein the means to cause the support surface tovibrate is attached to the cargo container.
 52. An active bulkheadcorner, as in claim 14, wherein the means to cause the support surfaceto vibrate is attached to the bulkhead.
 53. An active bulkhead corner,as in claim 14, wherein the means to cause the support surface tovibrate is attached to the cargo container.
 54. An active bulkheadcorner, as in claim 18, wherein the means to cause the support surfaceto vibrate is attached to the bulkhead.
 55. An active bulkhead corner,as in claim 18, wherein the means to cause the support surface tovibrate is attached to the cargo container.
 56. An active bulkheadcorner, as in claim 44, wherein the means to cause the support surfaceto vibrate is attached to the bulkhead.
 57. An active bulkhead corner,as in claim 44, wherein the means to cause the support surface tovibrate is attached to the cargo container.